This application is based upon and claims the benefit of priority from the prior Japanese Patent Application No. 11-318821, filed Nov. 9, 1999, the entire contents of which are incorporated herein by reference.
The present invention relates to an information recording medium which has a plurality of sector fields that record data, and in which a block is defined by a set of a predetermined number of sector fields, for example, a DVD (Digital Versatile Disk). The present invention also relates to an information recording apparatus and method for recording information on the information recording medium. Furthermore, the present invention relates to an information reproduction apparatus and method for reproducing information from the information recording medium.
In recent years, information recording media such as a DVD that features high-density recording have been extensively studied and developed. Such information recording medium has a plurality of sector fields which record data, and an ECC (Error Correction Code) block is defined by a set of a predetermined number of sector fields.
Even when data is recorded on some sector fields of such information recording medium, the entire ECC block which includes target sector fields as a recording destination is read. Of the read ECC block data, target data patches a portion corresponding to the target sector fields, and the ECC block is re-arranged and recorded in the original ECC block. Such recording in units of sector fields is called read-modify-write.
Such read-modify-write is suitable for recording PC data that does not require real-time processes but is not suitable for recording AV data that places an importance on real-time processes since it is relatively time-consuming. In order to avoid read-modify-write, data can be recorded in units of ECC blocks.
Upon recording AV data, in general, initial defect management that registers initial defects by format and certify is not made. That is, defects remain on the recording space. Upon recording AV data, it is important to continue recording without any interruption ignoring some errors (defects) in sector fields as a recording destination.
However, when both PC and AV data are recorded on a single information recording medium, especially, when PC data is overwritten on AV data, the error rate increases upon read-modify-write due to the absence of defect management. That is, ECC block data cannot be read out upon read-modify-write, that ECC block consequently cannot undergo a replacement process, and read-modify-write terminates abnormally.
The present invention has been made to solve the aforementioned problems, and has as its object to provide the following information recording medium, information recording apparatus, information recording method, information reproduction apparatus, and information reproduction method:
(1) an information recording medium which can reduce the error rate upon read-modify-write when data is overwritten in units of sector fields on data recorded in units of ECC block data;
(2) an information recording apparatus and method which can reduce the error rate upon read-modify-write when data is overwritten in units of sector fields on data recorded in units of ECC block data; and
(3) an information reproduction apparatus and method which can reduce the error rate upon read-modify-write when data is overwritten in units of sector fields on data recorded in units of ECC block data.
In order to solve the above problems and to achieve the above object, the information recording medium, information recording apparatus, information recording method, information reproduction apparatus, and information reproduction method according to the present invention have the following arrangements.
(1) An information recording medium of the present invention is an information recording medium which has a plurality of sector fields that record data, and in which a block is defined by a set of a predetermined of sector fields,
wherein each sector field has an identification information area for storing one of first identification information indicating that data is recorded with a first integrity level, and second identification information indicating that data is recorded with a second integrity level lower than the first integrity level.
(2) An information recording apparatus of the present invention is an information recording apparatus for recording information on an information recording medium which has a plurality of sector fields that record data and respectively have identification information areas, and in which a block is defined by a set of a predetermined of sector fields, comprising:
recording means for recording, in the identification information area, first identification information indicating that data is recorded with a first integrity level when desired information is recorded with the first integrity level on the information recording medium, and recording, in the identification information area, second identification information indicating that data is recorded with a second integrity level when desired information is recorded with the second integrity level on the information recording medium.
(3) An information recording method of the present invention comprises:
the step of, when desired information is recorded with a first integrity level in an information recording medium which has a plurality of sector fields that record data and respectively have identification information areas, and in which a block is defined by a set of a predetermined of sector fields, recording data in each identification information area with the first integrity level; and
the step of, when desired information is recorded with a second integrity level in the information recording medium, recording data in each identification information area with the second integrity level.
(4) An information reproduction apparatus of the present invention is an information reproduction apparatus for reproducing information from an information recording medium which has a plurality of sector fields that record data, and in which each sector field has an identification information area that records one of first identification information indicating that data is recorded with a first integrity level, and second identification information indicating that data is recorded with a second integrity level lower than the first integrity level, and a block is defined by a set of a predetermined number of sector fields, comprising:
reproduction means for acquiring information that pertains to integrity by reproducing the first identification information or second identification information from the identification information area.
(5) An information reproduction method of the present invention is an information reproduction method for reproducing information from an information recording medium which has a plurality of sector fields that record data, and in which each sector field has an identification information area that records one of first identification information indicating that data is recorded with a first integrity level, and second identification information indicating that data is recorded with a second integrity level lower than the first integrity level, and a block is defined by a set of a predetermined number of sector fields, comprising:
the step of acquiring information that pertains to integrity by reproducing the first identification information or second identification information from the identification information area.
Additional objects and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The objects and advantages of the invention may be realized and obtained by means of the instrumentalities and combinations particularly pointed out hereinafter.